1800÷5×62
90+186-84÷42
491-(25+20)×4
365×8×125×2
57×48+52×57
69×[(580-445)÷9].
解:(1)1800÷5×62,
=360×62,
=22320;
(2)90+186-84÷42,
=90+186-2,
=276-2,
=274;
(3)491-(25+20)×4,
=491-45×4,
=491-180,
=311;
(4)365×8×125×2,
=(365×2)×(8×125),
=730×1000,
=730000;
(5)57×48+52×57,
=(48+52)×57,
=100×57,
=5700;
(6)69×[(580-445)÷9],
=69×[135÷9],
=69×15,
=1035.
分析:(1)(2)(3)(6)依據四則運算計算方法:先算第二級運算,再算第一級運算,如果只含有同一級運算,按照從左到右順序就是,有括號先算括號里面的順序解答即可,
(4)運用乘法交換律和結合律即可解答,
(5)運用乘法分配律解答.
點評:(1)依據四則運算計算方法正確進行計算,(2)正確運用簡便方法解決問題,是本題考查知識點.